Effect of annealing temperature and atmosphere on aluminum-doped ZnO/Au/aluminum-doped ZnO thin film properties

•High-quality Al-doped ZnO (AZO)/Au/AZO transparent conducting oxide films•AZO films (30 nm) made by RF magnetron sputtering; ion sputtering for Au film (8 nm)•Effects of annealing temperature and atmosphere were analyzed.•Annealing process was employed to improve the properties of film.

This study investigated the effect of different annealing conditions on the electrical properties of aluminum-doped ZnO/Au/aluminum-doped ZnO thin films. The thin films were prepared using rf magnetron sputtering (for AZO) and ion sputtering (for Au). They were then annealed in atmospheres of vacuum, nitrogen, and oxygen at temperatures ranging from 100 to 400 °C in steps of 100 °C for 3 min. Two critical parameters of the multilayer films were the Au layer thickness and annealing conditions (influence of the annealing temperature and atmosphere). High-quality multilayer films (with an 8-nm-thick Au layer) with a resistivity of 6.34 × 10− 5 Ω cm and a maximum optical transmittance of 92.3% were obtained upon annealing the films at 200 °C in vacuum. These parameter values indicate that the films are a potential candidate for high-quality electrodes in various displays.